A bow string peep sight of this type is described in U.S. Pat. No. 4,454,857, said peep sight comprising a wheel having a central elongated, hollow hub portion extending perpendicular to the plane of the wheel for receiving the bow string. The wheel is provided with a continuous rim portion connected to the hub by spokes and leaving a transparent sighting area between the rim portion and the hub. The wheel of the known peep sight is plane at one side but is provided on the opposite side with a conical recess ensuring said sighting area to be sharp-edged at its outer limitation. When such a peep sight is tilted owing to the drawing of the string a sighting aperture is revealed--provided the eye is close to the sight--between the hub and rim, said aperture being limited inwards by a straight line defined by the outer face of the hub and outwards by a relatively long elliptic arc defined by the inner edge of the rim portion. In far the most cases, a spoke is positioned in the visual fields of the sighting apertures. However, the presence of a spoke within the used sighting aperture blurs the view through said aperture to a certain degree. Furthermore, the elliptic arc limiting each sighting aperture outwards has a close resemblance to a semi-circle and, therefor in most cases the sighting aperture is too large for ensuring a correct aiming. In most cases, it is inconvenient that two sighting apertures are formed--one on each side of the string--since the wrong aperture may be chosen especially when the aiming period is very short.